Picture this: After a lightning-short campaign with few civilian casualties, Saddam Hussein is removed from power and the crowds in Baghdad cheer US and allied troops. A multinational force preserves the peace. A UN administrator reorganizes the Iraqi government and monitors elections. Within a few years, only a handful of American troops remain. In Iran, democratic forces take heart from the change next door. Syria adjusts to the new reality. Even Saudi Arabia establishes an elected advisory council. After difficult negotiations, a peaceful and democratic Palestinian state is created, and terrorism in the Islamic world tapers off. That is President Bush's picture of the future.
Or try this: The war is longer and bloodier than expected. After initial relief at the removal of Hussein, Iraq's Shiite, Sunni, and Kurdish factions fight for power. Large numbers of US troops are tied down preserving order. Lacking a UN flag, they're widely portrayed as imperialists. Terrorist attacks increase. Hard-liners in neighboring Iran, citing the American threat and taking heart from North Korea's unchecked progress, crack down on their democratic opposition and accelerate Iran's nuclear-weapons program. Syria hedges its bets. Citing continued violence in the region, the Likud government in Israel decides it cannot risk the establishment of a Palestinian state. Saudi Arabia asks the US to remove its bases. Terrorism increases in the Islamic world. That is the antiwar movement's picture of the future.
The truth probably lies somewhere between these two portraits. Where it comes out depends on such things as the length of the war, the extent of civilian casualties, how broad a coalition the US develops, and to what extent it goes it alone in reconstructing Iraq. Given its history and internal divisions, Iraq - postwar - is unlikely to look like democracy as we know it, but it will be a better and more pluralistic regime than now exists. Some Islamic terrorists will use the occupation of Iraq to recruit supporters who will try to kill Americans. US military success may lead Iran and Syria to temper their policies, but if Mr. Bush is unable to persuade Ariel Sharon to reach a compromise acceptable to the Palestinians, the map of the region may change less dramatically than the optimists hope.
Behind these contrasting pictures lies a dilemma that has bedeviled US foreign policy since the days of President Woodrow Wilson. How far should we go in using our military forces to make the world safe for democracy? Dedication to the broad values of democracy and human rights is part of America's "soft" or attractive power and an essential part of its foreign policy. But democracy is a fragile plant that requires carefully cultivated soil. It is not easily transplanted. Of the places where the US has sent troops in the past half century, only a minority of the interventions resulted in democratic governments.
Optimists cite the role of US military occupation in the democratization of Germany and Japan after World War II. But conditions in the Middle East today are not like Germany and Japan in 1945. Both those countries had large middle classes, prior experience with democracy, and a prolonged and largely unopposed American military presence. South Korea and Taiwan are often cited as more recent success stories of less-developed countries that have made the transition to democracy. That is true, but democracy began to flourish in those countries only after two decades of economic growth had produced a middle-class society that could no longer be easily ruled by authoritarian methods.
The debate over democracy as a foreign-policy objective does not mirror the usual left-right divisions in American politics. Conservatives are divided on the issue. Traditional realists warn that the neoconservative "Wilsonians of the Right" may, like their left-wing predecessors, entangle the US in a hell of good intentions if it bites off more than it can chew.
Making the Middle East safe for democracy is a worthy goal, but it will require patience and a wide range of instruments beyond military force. Risks and costs can be reduced only if the US builds a consensus, shares tasks with others, and resists the impatient unilateralist temptation to go it alone.
• Joseph S. Nye is dean of Harvard's Kennedy School of Government and author of 'The Paradox of American Power: Why the World's Only Superpower Can't Go It Alone.'